Design of a bolometer for total-energy measurement of the linear coherent light source pulsed X-ray laser

✍ Scribed by S. Friedrich; L. Li; L.L. Ott; Rajeswari M. Kolgani; G.J. Yong; Z.A. Ali; O.B. Drury; E. Ables; R.M. Bionta

• Publisher: Elsevier Science
• Year: 2006
• Tongue: English
• Weight: 148 KB
• Volume: 559
• Category: Article
• ISSN: 0168-9002
• DOI: 10.1016/j.nima.2005.12.139

✦ Synopsis

We are developing a cryogenic bolometer to measure the total energy of the linear coherent light source (LCLS) free electron X-ray laser to be built at the Stanford Linear Accelerator Center. The laser will produce ultrabright X-ray pulses in the energy range between 0.8 and 8 keV with $10 12 photons per $200 fs pulse at a repeat interval of 8 ms, and will be accompanied by a halo of spontaneous undulator radiation. The bolometer is designed to determine the total energy of each laser pulse to within o0.1%, taking into account thermal and mechanical stress to prevent melting in the LCLS beam due to its high energy density. We propose to use a magnetoresistive Nd (1Àx) Sr x MnO 3 sensor array at the metal-insulator transition, where the composition x is adjusted to produce the desired transition temperature. We discuss design considerations and material choices, and present numerical simulations of the thermal response.